Scalable and Reconfigurable All-Optical VPN for OFDM-Based Metro-Access Integrated Network

In this paper, we propose an orthogonal frequency division multiplexing (OFDM)-based metro-access integrated network (MAIN), which enables scalable all-optical virtual private network (VPN) communication for the first time. Two types of VPN communication, inter-VPN and intra-VPN, are introduced in the proposed MAIN. By placing the VPN light sources in central office (CO) and cascading a wavelength de-multiplexer (DeMUX) with an M* M optical on-off in CO and each central node (CN), the centralized dynamic management of the VPN sub-bands and communications can be achieved in CO. Meanwhile, by employing the proposed VPN sub-bands allocation scheme and recycling process, the scalability and the reconfigurability of all-optical VPN are significantly improved. Theoretical analysis of VPN scalability has been conducted to obtain the minimal and maximal numbers of the multi-VPNs communication that the MAIN can support simultaneously. Besides, the performance degradation of OFDM modulation introduced by the broadened line-width of laser has been studied and discussed. The intra-VPN and inter-VPN communications at 10-Gbit/s with 16 quadrature amplitude modulation in the proposed OFDM MAIN system are successfully simulated and the results show the feasibility of the proposed scheme.